Noctilucent reflective helmet

ABSTRACT

A helmet used for securing traffic safety for the pedestrians at night which is possessed of a noctilucent reflector affixed onto the outer surface thereof consisting of a reflective layer formed by mixing a highly reflective powdered metal and transparent granules, which make the helmet extremely easily recognizable from all the directions in the dark.

United States Patent [191 Komine Nov. 6, 1973 NOCTILUCENT REFLECTIVEHELMET [56] References Cited [75] Inventor: Shinsuke Komine, Tokyo,Japan UNITED STATES PATENTS 7 2 2,218,909 /1940 Gill 117/35 X l 3]Ass'gnee gzr 'zi af g gl iz Auto 2,143,946 1/1939 Hunter 117/35 R I y p2,354,049 7/1944 Palmquist 117 35 x [22] Filed: July 8, 1971 3,253,9715/1966 Garling 117/35 A 1,387,424 8/1921 Merritt 117/35 R I [21] Appl.No.: 160,951

Related US. Application Data Primary Examiner-A1fred L. Leavitt [63]Continuation of Ser. No. 727,231, May 7, I968, Y- Oshemff abandoned. I

57 ABSTRACT Forelgn Apphcatmn Pnomy Data A helmet used for securingtraffic safety for the pedes- Feb. 28, 1968 Japan 43/15515 trians atnight which possessed noctilucent flector affixed onto the outer surfacethereof consisting [52] US. Cl 117/33, 117/35 R, 2/175 of a reflectivelayer formed by mixing a high), reflec [51] 1111. C1 A421) 3/00, B44d1/16 five powdered metal and transparent granules which [58] Flew ofSearch 1 17/35 35 make the helmet extremely easily recognizable from allthe directions in the dark.

2 Claims,'-2 Drawing 'Figures PATENIEUNUY 6 ms F I G.

FIG.2

INVENTOR.

NOCTILUCENT REFLECTIVE HELMET This application is a continuation ofapplication Ser. No. 727,231 filed May 7, 1968, now abandoned.

The present invention relates, generally speaking, to a helmet and amethod of producing same, and, more particularly, to a helmet used forthe purpose of securing traffic safety for the pedestrians at night byvirtue of providing the helmet over its entire surface with a kind ofreflector.

Conventional helmets publicly known presently as serving for the purposeof maintaining the safety of night pedestrians are made up by pasting aso-called reflector, that is usually a strip of noctilucent texture,onto the middle part of the external surface of the helmet proper in thedirection before and behind with a suitable, publicly known adhesive assecurely as if incorporated with the helmet. Referring to the saidnoctilucent texture, it is specially manufactured by Kyoto Orimono(Textile) Co. Ltd. seated at Sakyo-ku, Kyoto City,'Japan, and itsstructure is such that the texture face is coated with a special resinso as to constitute thereover a reflective layer to which very finegranular lenses ar made to adhere uniformly and in in parallel rows.

As regards, however, the helmets having such a reflector asaforementioned, because of the fact that the reflector is provided onlyon the middle part of the helmet proper, it can hardly be caught intoview in the angle of vision otherithan a certain fixed direction only,they are far from serving the purpose of the maintenance of safety fornight pedestrians, still as a problem awaiting solution. Accordingly,for the solution of the problem, the men in the art have attempted topaste the said reflector onto the entire surface of the helmet proper.Nevertheless, it has become explicit through copious experiments thataffixing the reflector, that is, the said noctilucent texture, uniformlyand evenly to the semi-spherical helmet is extremely difflculttechnically and, moreover, satisfactory helmets have as yet failed to berealized despite of a great deal of time and labour expended in the saidaffixation of the reflector.

Furthermore, in the aforementioned helmets, such a thing would occuroften with the pasting of the reflector to the helmet proper that theadhesive or the like, as means for the adhesion of reflector, is apt tobe applied to parts other than the portion to be applied so that thework of affixing might be considerably hampered.

The principal object of this invention is to pro'vide'a helmet soadapted as to exhibit at its maximum the effect of maintaining thetraffic safety of night pedestrians by affixing a reflector whosereflection coefficient is extremely high onto the whole of the externalsurface of the helmet proper.

The other object of this invention is to provide a helmet so adapted asto have the reflector evenly and uniformly applied to the whole of theexternal surface of the helmet proper.

Another object of this invention is to provide a helmet so adapted thatthe work of applying the reflector to the entire surface of the helmetproper is very simple requiring no skill by any means.

Another object of this invention is to provide a helmet so adapted thatthe time and labour required for the work of applying the reflector tothe entire surface of the helmet proper can be greatly reduced.

Still another object of the present invention is to provide a helmet soadapted, in affixing the reflector to the whole surface of the helmetproper, that the necessary material and cost can be saved and reduced byusing no adhesive means.

For the purpose of achieving the foregoing varied objects of theinvention, the present invention will be characterized by applying tothe entire external surface of the helmet proper a reflector which iscomposed of transparent granules and a reflective layer formed by mixingan adhesive resin material with a highly reflective powdered metal.

The helmet of this invention has, moreover, proved as a result ofexperiments that because of thereflective layer and the transparentgranules which constitute the reflector the light reflective coefficientis markedly promoted so that the helmet can be certainly recognized froma distance as far as 200 to 300 meters even at the time of dusk that ismost difficult for identification or recognition.

It is believed firmly that other objects and advantages of the inventionwill become apparent and be fully understood from the followingdescription taken in connection with the appended drawings in which:

FIG. 1 is a vertically cross-sectional view schematically showing thehelmet according to this invention (wherein the binding straps are shownin two-dot chain lines); and

FIG. 2 is an enlarged cross-sectional view showing fragmentally theessential portion of the helmet.

Now, referring to FIG. 1 for describing the outline of the helmet madeaccording to this invention, numeral 10 in the figure denotes the helmetproper which is shaped like an ordinary cap composed of a metallicmaterial or a synthetic resin material or other similar material. Assuch a helmet as this is publicly known in itself, no detaileddescription will be made herein. The said helmet proper 10 is providedwith common binding straps 11a, lllb which are securely attachedincorporatedly thereto through their one end by known suitable means,their other end being free but affixed to binding metals 11c, 11drespectively; these straps 11a, 11b as well as binding metals 11c, 11dare very well known therefore being shown just schematically in theappended drawings.

The said helmet proper 10 is also provided on its entire externalsurface with a reflector 14 consisting of innumerable transparentgranules l3 and a reflective layer. 12 which is to be fully describedlater. The said reflective layer 12 is composed of by mixingfinepowdered aluminium or a powdered reflective metal 12a and 12b in theform of crystals of basic lead carbonate with an adhesive resin materialcomposed mainly of a polymer of acrylic acid ester such as, for example,the polymer of ethyl acrylate and butyl acrylate. In this embodiment ofthe invention, acrylic acid esters are adopted for use as the saidadhesive resin material but, in the present invention, the adoption ofthe resin material is not limited to the said acrylic acid esters alone.For example, suitable resin materials such as vinylic resins like styrolresin or synthetic rubber or the like may be as well employed alike.

, Now, the process of affixing the reflector l4 evenly and uniformlyonto the entire external surface of the helmet proper 10 will beillustrated in reference to FIG. 2. In the first place, a kneadedmaterial to be used as the reflective layer is manufactured by mixing 24percent of the said acrylic acid ester polymer, for example, and 4percent of fine-powdered aluminium or other similar, highly reflective,powdered metal, and regulating the resultant mixture with 72 percent ofa ketonic solvent such as acetone, xyrol or the like so as to have thesolid content of the acrylic acid ester polymer and the mineral contentmaintained at 24 percent and 4 percent respectively. In addition, asmeans for regulating the said kneaded material, a publicly knownkneader(not shown) or the like may be employed.

The kneaded material thus obtained will thence be coated over the helmetproper 10; for this occasion, there should first be provided ahopper-like pouring member(not shown) to be located in the central partof the external surface of the said helmet proper 10. Now, the saidkneaded material is slowly put into the said pouring member in amountsof 20 to 30 grams as per one helmet; the kneaded material thus poureddown will thereupon be dropped first onto the center of the externalsurface of the helmet proper 10, and the kneaded material thus droppedwill flow evenly over and along the curved surface of the helmet proper10 by virtue of its own fluidity and 3,000 to 5,000 C.P. viscositycharacteristic, so that a coated, reflective layer 12 having an equalthickness all over may be obtained.

Further, as means for the said coating, spray coating or brush coatingor the like may also be employed, but it has been found as a result ofexperiments that the formation of a uniform smooth reflective layer isvery difficult to be realized due to the high viscosity of the saidkneaded material with these conventional means.

When the reflective layer 12 is formed any way over the entire externalsurface of the helmet proper 10, it is e at 19s o 5&9 7 ut attbs qmmra Qabout 25C, whereupon the transparent granules 13 are dispersed through a200-mesh glass dispersing sieve(- not shown) from the top of the saidreflective layer 12, preferably from the position as high as 30 cm. Atthis occasion, the said helmet proper 10 is brought to be borne by arotary support member (not shown) which has been connected with a drivemechanism such as motor through a gear; the said rotary support memberis rotated by transmitting the driving force of the said drive mechanismthereto through the said gear upon operating the said drive mechanism,which is very well known therefor being not shown in the drawings. Therotation velocity of the said rotary support member will be 10 rpm inpractice while the rotation number of the helmet proper 10 from thestart to the termination of dispersion of the transparent granules willbe more or less five times. Further, the refractive index of the saidtransparent granules 13 will be in the range of 1.7 to 2.1, especiallypreferably 1.9, and the diameter of the said transparent granules 13will be in the range of 40 to 80 microns, especially preferably 50microns.

When the said transparent granules 13 have been thus dispersed, they aredried at the temperature of 50C for 10 minutes, followed by effectingfurther thereon a heat treatment for 3 minutes at 120C, so that areflector can be satisfactorily applied onto the whole of the externalsurface of the helmet proper 10.

Moreover, another advantage obtainable from the treatment asaforementioned will be in that the powdered reflective metal adheres toand along the periphcry of the portion where the transparent granules 13are imbedded in the reflective layer 12, and that 60 percentapproximately of the entire surface of the transparent granulesdispersed is imbedded within the reflective layer 12. Having such aninterrelation with each other, the reflector composed of the reflectivelayer and the transparent granules is provided as affixed onto theentire external surface of the helmet proper, and thus the light raysfrom every direction of the helmet may be caught and the returnreflection may be achieved to be effectuated. Another further advantagewill be in that the surface hardness of the helmet proper can beoutstandingly enhanced so that damages on the external surface thereofcaused by frictions or impacts may be prevented.

I claim:

1. A method of forming a helmet made of metallic or synthetic resinmaterial having a reflector affixed to the entire external surfacethereof, said reflector being composed of a reflective layer havingtransparent granules partially embedded therein, said method comprisingthe steps of providing an adhesive resin composition comprising anadhesive resin, a reflective powder, and a solvent for the resin, saidcomposition having a viscosity of about 3,000 5,000 centipoises; pouringsaid composition onto the center of the external surface of said helmetin a quantity of about 20 30 grams per helmet from a pouring memberpositioned above the central portion of the external surface of saidhelmet so that said composition will flow evenly over said surface toform a reflective layer of substantially uniform thickness thereover;maintaining said reflective layer at a temperature of about 25C forabout 5 7 minutes; dispersing transparent granules onto said reflectivelayer through a 200 mesh glass dispersing sieve from a position as highas 30 cm above said layer while rotating said helmet on the order ofabout 5 times with a rotational velocity of about 10 rpm so that saidgranules are dispersed evenly onto the entire curved surface of saidreflective layer; drying said layer with the granules thereon at atemperature of about 50C for about 10 minutes; and then heating saidlayer and granules for about 3 minutes at about 120C.

2. A helmet made of metallic or synthetic resin material having areflector affixed to the entire external surface thereof, said reflectorbeing composed of a reflective layer having transparent granulespartially embedded therein, said reflective layer being of substantiallyuniform thickness over the entire external curved surface of said helmetand being the dried residue of an adhesive resin compositioncomprisingabout 24 percent of an acrylic acid ester polymer, about 4 percent of.reflective aluminum powder, and about 72 percent of a ketonic solvent,said composition having a viscosity of about 3,000 5,000 centipoises atthe time it is uniformly spread over said surface; and said transparentgranules having a refractive index of about 1.7 2.1 and diameters ofabout 40 microns, said granules being uniformly dispersed about saidreflective layer, approximately 60 percent of the entire surface of saidtransparent granules being embedded within said reflective layer.

2. A helmet made of metallic or synthetic resin material having areflector affixed to the entire external surface thereof, said reflectorbeing composed of a reflective layer having transparent granulespartially embedded therein, said reflective layer being of substantiallyuniform thickness over the entire external curved surface of said helmetand being the dried residue of an adhesive resin composition comprisingabout 24 percent of an acrylic acid ester polymer, about 4 percent ofreflective aluminum powder, and about 72 percent of a ketonic solvent,said composition having a viscosity of about 3,000 - 5,000 centipoisesat the time it is uniformly spread over said surface; and saidtransparent granules having a refractive index of about 1.7 - 2.1 anddiameters of about 40 - 80 microns, said granules being uniformlydispersed about said reflective layer, approximately 60 percent of theentire surface of said transparent granules being embedded within saidreflective layer.